Conventionally, physicians, gastroenterologists, or other healthcare professionals (“physician(s)”) utilize luer assemblies for quickly, securely, and reliably connecting medical devices to be used in many medical or surgical applications. For instance, physicians use luer assemblies to connect syringes at one end and catheters at the other end in order to form fluid flow conduits from the syringe to the catheter and the catheter into a body passageway within a patient.
The term “passageway” is understood to be any lumen, chamber, channel, conduit, opening, bore, orifice, flow passage, duct, or cavity configured for allowing the conveyance, regulation, flow, or movement of fluids, liquids, and/or gases such as, by way of example and not by way of limitation, bodily fluids and/or gases of or to an animal. As an example, devices utilizing luer assemblies and catheters have become widely accepted in the medical field for use in the passageways of an aorta, artery, bile duct, blood vessel, bronchiole, capillary, colon, esophagus, fallopian tube, gastroduodenal, gastroesophageal, gastrointestinal, heart, intestine, pylorus, trachea, ureter, urethra, vein, and other locations in a body (collectively, “vessel”) to name a few.
In order to further provide a background of the invention, catheters will be discussed next. Then, syringes will be discussed. Following the discussion on catheters and syringes, an overview of luer assemblies will be reviewed as a background of the invention. These components are only provided for background purposes, and not as limitations of the invention.
Catheter
A catheter, in general terms, is a tubular device having proximal and distal ends with openings at or near those ends and defining a lumen. As is conventional, the term “distal” means away from the physician when the catheter is being or has already been inserted into a patient, while the term “proximal” means closest to or toward the physician when the catheter is being or has already been inserted into a patient. Catheters may have one lumen (e.g., a single-lumen catheter) or more than one lumen (e.g., a multi-lumen catheter) such as, by way of example only, two lumens. In order to accommodate most of its medical uses, the catheter generally can fall into two categories: a thin, flexible tube (a “soft” catheter) or a larger, solid tube (a “hard” catheter).
The process whereby the physician inserts a catheter is commonly known as catheterization. The catheter lumen allows fluids to enter or, as desired, exit a vessel passageway within a patient. What is commonly known as a central line, for example, is a catheter assembly that provides a conduit for delivering drugs or fluids to a large-bore catheter positioned either in a vein near the heart or just inside the atrium of the patient. Likewise, the catheter lumen may allow gases to pass into the vessel passageway, such as to distend the vessel for surgery, either directly through the catheter lumen or through intervening parts or devices associated with the catheter.
Catheterization has many other medical and surgical applications in addition to the central line assembly and those mentioned above. By way of example only and not by way of limitation, placing a catheter into a particular vessel passageway may facilitate many medical procedures: (1) draining urine from the urinary bladder as in urinary catheterization (i.e., a Foley Catheter) or even when the urethra is damaged as in the procedure known as super-pubic catheterization; (2) administering intravenous fluids, medication, or parenteral nutrition; (3) practicing angioplasty in order to unblock a blood vessel or artery; (4) injecting dye or radio-opaque contrast into blood vessels or other structures to visualize abnormalities, as in cardiac catheterization, which is part of coronary angiography; (5) directly measuring blood pressure in an artery or a vein; (6) infusing local anesthetics and other drugs for epidural anesthesia; and (7) suctioning unwanted fluids from the airway (usually with a hard catheter).
Syringe
An optional syringe may be used directly or indirectly with a luer assembly (discussed below) for carrying or removing fluids, liquids, and/or gases such as, by way of example and not by way of limitation, intravenous fluids, blood, medications, and/or gases. A typical syringe comprises a plunger fitted to a proximal end of a tube, called the barrel, the barrel having a small opening at or near its distal end. The barrel of a syringe may be made of plastic or glass and usually has graduated marks indicating a volume of fluid and/or gases in the syringe.
While glass syringes may be sterilized by the use of an autoclave, modern medical syringes are typically made from plastic. Disposing plastic syringes tends to be more cost-effective than sterilizing glass syringes. Also, disposing plastic syringes in lieu of sterilizing glass syringes may reduce the risk of spreading blood-borne diseases.
Physicians use syringes to transfer or remove liquids or gases to or from otherwise inaccessible areas within a patient. Syringes operate on the principle of negative pressure (e.g., suction) being used to fill the barrel with a substance at the syringe's distal opening as the physician draws out the plunger, and expelling the substance when the physician depresses the plunger. The process of administering a substance with a syringe and needle is called an injection.
Luer Assembly
Luer connectors, luer type fittings, and other medical connector systems (individually and collectively, “luer assemblies”) provide fluid flow conduits for use in medical or surgical applications. These luer assemblies may come in many types. Generally stated, luer assemblies include a male member and female member configured to be joined together, each member configured to have proximal and distal ends with openings and each defining a lumen therethrough such that the physician may connect the male and female members directly or indirectly through intervening parts. Typically, though not always, the male member has a slightly tapered distal body designed for inserting into the female member, and the female member has a similarly tapered bore for receiving the male member.
One luer assembly for instance, commonly called a luer slip, comprises a friction fit between a tapered distal end of a male member that has been inserted into a corresponding tapered proximal bore within a female member. Another illustrative type of luer assembly, commonly called a luer lock connection, includes a female luer distal end with an annular flange having internal threads and a male luer proximal end with a threaded outer surface for engaging the female threads. Alternatively, the male member has a distal end with a flange, protrusion, or rib for interlocking with a corresponding flange, recess, or rib at or near the proximal end of the female member.
The luer assembly may also comprise an optional collar to help join the male and female members. For instance, the optional collar might comprise internal threads to mount the female luer member and maintain the connection between the male and female members and substantially prevent fluid leakage between the male and female members. The collar threads might draw the male and female members together or otherwise engage corresponding threads in one or both of the male or female members. With one design, the physician rotates the collar about the male and female members by hand.
In addition, the male luer member may have an optional distal catheter hub for securing an optional cannula. Generally stated, the optional cannula is a tube that, when inserted into the body of a patient directly—or indirectly by inserting into a lumen of a catheter that in turn is inserted into the body of a patient directly—is typically used either to withdraw fluid or insert medication. If inserted directly into the patient, the optional cannula normally comes with a trocar (a sharp pointed needle-like device) attached to the cannula's distal end for puncturing the dermis of a patient in order to be used percutaneously at the intended space. When a cannula is attached to a distal end of a male luer member and is intended to be inserted into a catheter, then the cannula may be rigid, flexible, or partially flexible and configured without the trocar (or with a less sharp trocar) so as not to puncture the catheter inner walls upon insertion into the catheter lumen. Furthermore, the male luer member optionally may have a proximal syringe hub for joining to a syringe.
Luer assemblies are well known in the medical device field. Indeed, luer assemblies are ubiquitous in hospitals where they commonly, for example, connect a syringe outside the patient with a catheter inserted, or intended to be inserted, within the patient's vessel passageway.
Typical procedures for using luer assemblies with catheters, however, currently are limited by the variable of whether the catheter is a single lumen catheter or a multi-lumen (e.g., two or more lumens) catheter. When the catheter has a single lumen, conventional methods comprise steps that require the catheter proximal end to be flared so as to mate with the tapered distal end of the luer assembly. In order to expand or otherwise open the catheter proximal end outwardly, an iron rod typically is inserted into the catheter lumen, wherein the iron rod is heated before or after insertion into the catheter lumen. One problem with using the flaring rod to flare the catheter proximal end, however, is that, if too much heat is used or for too long, the catheter may burn or degrade. In addition, the catheter lumen needs to be sized for the iron rod, so the physician may need to keep on hand many iron rods of different sizes.
The present invention solves these and other problems by providing a select slit at a catheter proximal end portion of a single lumen catheter through the catheter lumen in order to form tails at the proximal end portion. The tails are disposed between operatively coupled first and second connectors.
With a multi-lumen catheter, a cannula secured to the male member distal end typically inserts into one lumen with an interference fit and thereby centers the male member relative to that lumen. This procedure for attaching the catheter and luer assembly provides for easy assembly, but often has compromised joint integrity whereby the luer connection can loosen and possibly even disconnect. Where the joint integrity fails totally or even in part, fluid leakage may result and, in some cases, disrupt the flow from the syringe (or other fluid container located at the luer assembly proximal hub) to the patient at the luer assembly distal end. Accordingly, there is a need to provide a method for attaching catheters and luer assemblies that allows for strong joint strength to multi-lumen catheters.
The present invention solves these and other problems by providing a select slit at the proximal end portion of the multi-lumen catheter through one or more of the lumens in order to form tails. The tails are disposed between operatively coupled first and second connectors.
In addition to providing strong joint strength, these novel methods and catheter connector assemblies as taught herein have the added benefit of being used with readily available luer assemblies and catheters with which physicians are already familiar. Also, when operatively coupled between the first and second connectors, the tails provide a quick connect/disconnect, joint integrity, and sealing properties.